This is a package for sublime text 3. It includes syntax highlighting the best that i could for cogs even in their most complex of usages.
It also has Autocomplete definitions for all cog verbs. Unzip this file and drop it in: C:\Users\AcidRain_ssd\AppData\Roaming\Sublime Text 3\Packages\User. Obviously change AcidRain_ssd to your username